In a microscope, a microfabrication apparatus, a semiconductor manufacturing apparatus, and the like in which a charged particle beam is applied, a single-stage or a multistage multipole (such as 2-, 4-, 6-, and 8-multipole elements) is used in a deflector of the beam and an aberration corrector. In recent years, machining on the order of several tens of nanometer or monitoring on the order of subnanometer is performed by using these charged particle beam applied apparatuses, and controlling the beam with accuracy on the order of subnanometer are required. In the deflector and the aberration corrector integrated in these apparatuses, although final adjustment is performed electrically as a matter of course, the multipole needs to be assembled with high degree of mechanical accuracy as premises therefor. Otherwise, a parasitic multipole field which may cause an aberration in addition to a multipole field required essentially for deflection or aberration correction is generated, and hence a compensation coil may be required newly for a correction thereof, or fine adjustment independent for individual multipole elements may be required. In particular, the spherical aberration corrector and the chromatic aberration corrector are required to have assembly accuracy on the order of micrometer. As a method of forming the multipole with high degree of accuracy of the related art, PTL 1 discloses a method of setting a positioning member on an optical axis, pressing and fixing multipole elements against the positioning member, and then pulling out the positioning member when manufacturing the multipole. PTL 2 discloses a system of performing positioning of a multipole by arranging a spacer having a ball shape or a cylindrical shape on the inner side of a cylindrical housing. PTL 3 discloses a system of fixing individual multipole elements on a base plate with pins, and a method of fixing integral multipole elements, and then cutting off the same by a wire cutter. PTL 4 discloses a system of fixing a multistage-connected multipole element to a base block. PTL 5 discloses a system of forming an electrostatic multipole having a metallic layer provided on an inner wall of a cylindrical ceramics cylinder as an electrode.